Stop motion resetting device



Oct. 16, 1951 A. CRAWFORD Er AL STOP MOTION RESETTING DEVICE Filed Oct. 2l, 1949 5 Shests-SheeJ l Oct. 16, 1951 A. CRAWFORD ET A1. 2,571,211

STOP MOTION RESETTING DEVICE Filed Oct. y 21, 1949 5 Sheets-Shea?, 2

A. CRAWFORD El' AL STOP MOTION RESETTING DEVICE Oct. 16, 1951 5 Sheets-Sheet 5 Filed Oct. 2l, 1949 OC. 16, 1951 A, CRAWFORD ETYAL 2,571,211

STOP MOTION RESETTING EDEVICE Filed Oct. 2l, 1949 5 Sheets-Sheet 4 Oct. 16, 1951 A. CRAWFORD Er AL 2,571,211

sToP MOTION RESETTING DEVICE Filed oct. 21, 1949 5 sheets-sheet 5 Fatented ct. 16, 1951 UNETED STAT EATEN'' QF'FIC f 2,571,211 s'ror MotrioN RssE'rTn`\iGy DEVICE Application October 21, 1949, Serial No. 122,684

11 Claims. l

This invention relates to stop motions for knitting machines and more particularly to improvements in detector devices of the type adapted to interrupt operation of the machine upon appearance in the knitted product of defects such as holes, drop stitches, runs or the like.

A primary object of the invention is to provide a generally improved detector device of this character.

' Another and more specific object is to provide a detector device comprising means readily and rapidly operative after the device has been actuated in performance of its normal function for resetting the detector element or elements to operative state, said resetting means being of particular value in connection with detector devices having multiple detector heads.

The invention resides further in certain novel structural and mechanical details hereinafter described and illustrated in the attached drawings wherein:

Fig. 1 is a fragmentary vertical sectional view of circular knitting machine provided with a detector device in accordance with the invention;

Fig. 2 is an enlarged side elevational and partial sectional view of one of the several detector heads included in said device;

Fig. 3 is a top plan and partial sectional view of the detector head;

Fig. 4 is a rear elevational view of the head;

Fig. 5 is a sectional view on the line 5 5, Fig. 2;

Fig. 6 is a side elevational view of a detector head illustrating ya modification of the head shown in the preceding iigures;

Fig. '7 is a fragmentary front elevational View ofthe head shown in Fig. 6;

Fig. 8 is a sectional view on the line 8 8, Fig. l6;

Fig. 9 is a fragmentary plan view of a detector device of the character shown in Fig. 1 but employing a modied form of detector head;

Fig. 10 is a side elevational and partial sectional view of the device shown in Fig. 9;

Fig. 11 is a sectional View on the line II-I I, Fig. 9;

Fig. 12 is an enlarged plan view of the detector head shown in Fig. 9;

Fig. 13 is a fragmentary plan View of the head showing certain of the elements in positions assumed after actuation of the head;

Fig. 14 is a side elevational View of the detector head shown in Fig. 12; e

Fig. 15 is a vertical sectional view of the detector head;

Fig. 16 is a sectional View on the line lli-I6, Fig. 15;

Fig. 17 is a longitudinal sectional view showing the elements of one of the detector ngers;

Fig. 18 is a plan view of a detector head in still another form;

Fig. 19 is a side elevational view of the detector head shown in Fig. 18;

Fig. 20 is a sectional View on the line 2li-20. Fig. 19;

Fig. 21 is a vertical sectional view of the detector head shown in Figs. 18 and 19;

Fig. 22 is a section-al view on the line 22-22, Fig. 19;

Fig. 23 is a fragmentary sectional view showing elements of the device in diiferent relative positions;

Fig. 24 is a fragmentary plan view corresponding to Fig. 9, but on a reduced scale, illustrating a detector device having a slightly modied form of retracting mechanism;

Fig. 25 is a side elevational View, partly in section, of a modied form of detector device within the scope of the invention; and

Fig. 26 is a plan view of the assembly shown in Fig. 25.

With reference to Fig. l of the drawings, I is the rotary needle cylinder of a knitting machine and 2 the knitted tubular fabric which' passes downwardly from the needles 3 through the cylinder to the draw rolls 4. Supported on a rod 5 within the cylinder I and fabric 2 is the detector device forming the subject of the present invention.

This detector device comprises a cylindrical hub member 6 which is secured by a set screw 'I to the rod 5 and in which are adjustably secured a plurality of radially extending rods 8. The outer end of each of these rods lies in proximity to the fabric tube 2 and carries a detector head 9. In the present instance each head 9 comprises three detector fingers II, I2 and I3, and in operation the outer ends of these ngers press lightly against the inner surface of the rotating fabric tube. The lingers are slidably supported in the head structure and are urged outwardly by resilient means (hereinafter more specically described), so that when the end of one of the ngers encounters a hole of undue size in the fabric it will pass into such hole. The resulting lateral pull of the fabric on the finger will operate as hereinafter described to actuate the device to interrupt the operation of the machine.

With reference to Figs. 2 to 5 inclusive, which illustrate in detail one of the detector heads 9, the head comprises a base member I5 generally of channel form, as shown in Fig. 5, which is secured to the outer fiat end of the associated supporting rod 8 by means of screws I6 and I1. As shown in Fig. 2, the screw I6 is insulated from the base I by insulating sleeves and Washers indicated at I8; and the screw I1 is similarly insulated by suitable insulating elements I9 from the supporting rod 8. The base I5 is insulated by the same means from the support 8.

Slidably mounted in the base I5 is a member 2|, this member having at its rear end a depending arm 22 to which is secured a spring 23, the other end of this spring being anchored to the base I5. The spring thereby tends to retain the member 2| in an advanced position in the base as illustrated in Figs. 2 and 3. The member Z2 may be retracted in the base I5 against the action of the spring 23, and a retracting rod 24 connected to the member 2| by means of a screw 25 is provided for that purpose.

Pivotally mounted upon the forward end of the member 2| through the medium of a screw 2B is an element 2T, said element having an upwardly extending stein 28 in which are mounted detector fingers II, I2 and I3. As shown in Fig. 2 each of these ngers is supported in a tubular casing, 29, 3| and 32 respectively, which are adjustably secured in the stem 28 by screws 33. In each instance a spring 34 associated with the finger tends to hold it in an extended position in which the finger projects well beyond the forward end of its tubular casing. In practice, and as illustrated in Fig. l, these fingers will engage the inner surface of the tubular knitted fabric 2, the spring acting to hold the tips of the fingers in firm contact with the fabric.

Means is provided for retaining the element 21 in a vprt-:determined normal position on the member 2|, this means in the present instance consisting of the spring pressed ball and socket device illustrated at 35 in Fig. 2. In this normal position the fingers extend substantially radially with respect to the center of the hub member 6.

lThe forward end of the element 21 is centrally recessed, as shown in Fig. 3, and in normal position the said element under the influence of the spring 23 will rest against a pin 35 which extends upwm'dly from the base I5, the pincontacting the element 21 at the `bottom of the recess 31 in the latter. When the element 21 is angularly displaced about the pivot 2G from the normal position, one of the smoothly rounded forward surfaces 3S at the sides of the recess will exert a camming action against the relatively xed pin 35 which will cause a certain limited retractive movement of the member 2| in the base I5. The function of this limited retractive movement of the member 2| will be described below. A further retractive movement of the member 2|, effected as described above by way of the rod 24 will bring the sides of the member 21 into engagement with one or other of a pair of relatively fixed abutments 39 and 4| which extend upwardly from and at opposite sides of the base I5, the resulting pressureupon the element 21 being sufficient to turn it on the pivot 26 back to the original or normal position from which it was displaced. In Fig. 3 the angularly displaced position of the element 21 is shown in dotted lines and it will be evident with this position of the element, that when the member 2| is retracted in the base I5, the side of the element will be brought into engagement with the abutment 39 which will then exert a camming action to return the element to the normal position.

The angular displacement of the element 21 will be effected when any one of the detector 4 fingers under the pressure of the associated spring 34 will pass through a hole in the fabric 2. the rotary movement of the tubular fabric then carrying the lingers laterally with resulting displacement of the element 21.

Within the structure of the head 9 is an electric switch comprising a xed contact element 40 and a relatively movable contact 42. The element 40 is secured at the upper end of the screw I6 and is therefor insulated from the base I5 and electrically connected through the screw with the support 8. The movable element 42 is in the form of a lever pivotally supported upon a pin 43 extending upwardly from the base I5. A spring 44 exerts resilient pressure upon the element 42 to retain it in retracted position, as shown in Fig. 3, wherein it is disengaged from the contact element 46, the switch thereby being open. Depending from the member 2| is a pin 45 which, as best shown in Fig. 3,` is in operative association with the rear end of the member 42 so that when the member 2| is moved rearwardly from the normal advanced position of that member the pin 45 will engage the inclined surface 45 of the element 42 to thereby turn the said element in counterclockwise direction as viewed in Fig. 3 with the result that the turned-down forward end of the element 42 will be brought into engagement with the relatively fixed contact element 40 thereby closing the switch. As previously set forth this switch closing operation will be performed by camming action of the element 21 against the pin 35 occurring when the element 21 is displaced angularly from its normal position.

When, subsequently, the member 2| is fully retracted by means of the retracting rod 24. to thereby readjust the element 21 to the normal position as described, the pin 45 will be carried out of engagement with the element 42 which will then be returned to its normal retracted position by the spring 44. In the return movement of the member 2|, however, the pin 45 will engage the inclined terminal surface 41 of the element 42 and will be permitted to return to the normal position opposite the surface 46 of said element by pivotal movement of the said element in obvious manner. From the foregoing it will be apparent that any displacement of the element 21 from the normal position will result in an actuation of the switch 4D, 42. This switch will be associated with the stop motion of the machine in such manner that the aforesaid actuation of the switch will in turn actuate the stop motion.

In accordance with the invention all of the retracting rods 24 of the assembly shown in Fig.

1 will be connected to a common actuator. Thisdevice is illustrated in Figs. 9 and 10 which shows a detector device having modified detector heads but being otherwise of the same general construction shown in Fig. l. With reference to Figs. 9 and l0, therefore, the hub member 6 has mounted at the top thereof an annular element 5| in which is supported an apertured circular plate 52 for rotary movement about the axis of the supporting rod 5. The plate 52 carries a series of upwardly projecting pins 53. Pivotally mounted on the annular member 5I is a plurality of bell crank levers 54, one for each of the associated detector heads, and these bell crank levers are connected respectively to the retracting rods 9i] of the respective heads. The arms 55 of the bell cranks project inwardly over the outer edge of the plate 52 and into the path in which the pins 53 travel when the plate 52 is rotated. The arrangement is such that when the :said .plate 52 is rotated clockwise, as viewed in Fig. 9, the pins 53 by engagement with the inner arms 55 of the respective bell crank levers will swing these levers in a direction to retract the rods 24 and the slide members of the associated detector heads towhich the respective rods are connected. 'Ihe plate 52 may be rotated manually through an arm 56 on the latter and an operating rod 51. It will be apparent that actuation of this arm to turn the plate 52 will result in a simultaneous retraction of the slide members 2| or equivalent member of the said heads.

The annular element 5| is insulated from the supporting hub member 5 in the manner illustrated in Fig. 11 wherein the insulating elements are indicated generally by the reference numeral 58. The circuit of the switch 4|, 42 described above thus includes the supporting rod 8 extending from one of the terminal elements to the rounded hub member 6, and the retracting rod 24 extending from the other of said terminal elements to the ring 5| and thence through a lead wire 55 to the electrical actuating elements of the stop motion.

The modied detector head illustrated in Figs. 6, 7 and 8 is essentially the same as that described above with the exception that the spring 23 is replaced by a compression spring 5| which tends to urge the slide member 2| rearwardly to the fully retracted position indicated in broken lines in Fig. 5. A collar 62 on the support rod 8 limits this rearward movement of the slide. In order to normally retain the slide in the advanced position, a hook 63 is provided at the front of the element 21 which by interlocking engagement with the pin 36 holds the carriage in position against the pressure of the spring 6| so long as the element 21 is in the normal position. Angular displacement of the element 21 from this normal position, as described above,

will release the hook 63 from the pin 35 and will permit the spring 6| to move the member 2| together with the detector fingers to the retracted position. In this rearward movement the switch 4|, 42 will be actuated as described above.

During the retraction movement under action of the spring 6| the element 21 engages the abutment 39 or 4|, as the case may be, which returns the element 21 to the normal position. When, under these circumstances, the slide member 2| is returned to the advanced position, the hook 63 will again interlock with the pin 36 to retain the member 2| in position against the pressure of the spring 6|, the slightJ displacement of the element 21 as the hook 63 clears the pin 36 o-n the return movement being insuicient to entirely displace the spherical element 35 from the socket in the member 2| so that the element moves back immediately tothe normal position wherein the hook is interlocked with the pin. It will be noted that in this case the rod 50, which corresponds to the rod 9|] of theembodiment described above, will function to return the member 2| to the advanced position instead of retracting it and the connection between the rods 55 of the several heads andthe common actuating plate 52 will be such that the pins 53 of that plate will force the rods 50 outwardly instead of retracting them, as in the embodiment shown in Figs. 2 to- 5, when the plate is actuated.

In another embodiment, as shown in Figs. 9 to 16, inclusive, the nger supporting element 65 is pivotally mounted upon a member 60 slidu ably supported on a fixed bas 65, and a spring 61 associated with the pivot of the element 65 acts to retain the element in the normal position.y Displacement of the element 55, occurringA ment which is slidably mounted on the slide 59 and which is urged rearwardly by an associated spring 16 supported in the slide. When the pin 14 is interengaged with the hook 13 the member 15 will be held in the retracted position, shown in Fig. l5, against the pressure of the spring 16. In this retracted position of the member 15 a recess 11 on the underside of the member registers with an aperture 18 in the slide 6|) so that a spherical element 19 mounted in said hole may enter the recess 11 to occupy a relatively elevated position in said aperture. The sphere 19 is supported upon a spring arm 8| on the underside of the slide Bil which functions also as one terminal element of an electric switch, the other element 82 of the switch being the head of a bolt 83 which secures the base member 56 of the head to the supporting arm of rod 84. As shown in Fig. l5 insulating material-85 precludes electrical contact between the bolt 83 and the base member 66. A second screw 86 also serves to secure the base member 55 of the head to the support 85, and this screw is insulated by insulation means .49 from the support 84.

When the sphere 19 occupies the recess 11 the spring arm terminal element 8| will be elevated slightly above the terminal element 82 of the switch, as illustrated in Fig. l5. When the element 15 moves rearwardly under pressure of the spring 16 the sphere 19 wil1 be moved downwardly so as to depress the spring arm 8| to an extent making contact between this arm and the terminal element 82 of the switch. The element 15 will be permitted to move rearwardly by action of the spring 16 only after the pin 14 is released from the hook 13. This release occurs when the element 65 is angularly displaced from its normal position as indicated in dotted lines in Fig. l2. When the hook releases the pin 14 the element 15 moves rearwardly to the position shown in Fig. 13 wherein the pin 14 still engages the outer end of the hook 13. Since the pin 14 does not move out of contact with the hook 13 the pin functions through the hook as a restraining stop for the element 65 under pressure of the spring 61. Thus when the element 15 is returned to the normal position the spring 61 will cause the element 65 to return to its normal position wherein the pin 14 lies at the inside of the hook 13.

Return of the element 15 from the retracted to the advanced normal position is eiected by a rearward retraction of the slide member 55 through the medium of the retracting rod 90, see Fig. 9. A pin 81 extends upwardly from the support S4 in the path of this rearward movement and by engagement with the turned-down rear end of the element 15 will cause that element, as the member 62 is retracted, to return to the advanced normal position in which it is shown in Fig. l5. This adjustment of the element 15 not only permits the element 55 to return to the normal position but also permits the spherical element i5 to pass into the recess 11 so that the Switch arm may ex upwardly out of contact of the element 82. Reti-action of slide member 50, as described above, occurs against the pull of a spring 8, see Fig. 14, secured to the base member 68 and to the rear end of the member 60, as illustrated, and which functions to return the member to the normal advanced position when retracting rod 90 has been released.

In the embodiment of the invention shown in Figs. 18 to 22 inclusive, the detector nger support element 9| is pivotally mounted, as indicated at 92 in Fig. 21, upon a member 93 which is slidably supported in the base 94 of the head. In this instance the base 94 is secured to the supporting element 95 by screws 96, 96 which are both insulated, by means shown at 91 in Fig. 2l., from the support elements so that the base 94 is normally electrically disconnected from said support. The slide member 93 is normally retained in an advanced position by means of a spring 98 connected at 99 to the front of the base, and at its rear end to a depending arm on the slide member 93. The member S3 may be retracted against the action of the spring 98 by a retracting rod |02 of the character previously described.

In the normal advanced position of the member 93, and when the element 9| also occupies the normal position as determined by the spring pressed elements |03, the forward recessed face |04 of the element 9| is spaced apart from a pin |05 which extends upwardly from the support element 95. When the element 9| is angularly displaced from its normal position, as by means previously described, one or other of the forwardly projecting portions |06 of the said forward face |04 at the opposite sides respectively of the recesses will be brought into contact with the pin |05, as illustrated in Fig. 23. In this case the pin |05 forms one terminal element of an electric switch and the element 9| the other, so that when the latter element is displaced the switch will be closed to thereby actuate the stop motion of the machine in which the detector head is installed. Following such actuation the element 9| may be rotated to its normal position by retracting the member 93 to an extent bringing the side of the element 9| into engagement with one 01 other of the abutments 01 and |08 at the opposite sides oi the base member 94 as illustrated for ex ample in Fig. 20, the continued retraction of the slide 93 forcing the element 9| to turn to the normal position. When the slide member 53 is then released and is returned by action of the spring 93 to the normal advanced position the element 9| will occupy its original spaced relation to the pin |05.

The embodiment oi Fig. 24 corresponds generally to that of Fig. 9 with the exception that in this case the retracting rods |06 (which co1'- respond to the rods Q0 of the embodiment of Fig. 9) are pivotally connected directly to the rotary plate |01 (piate 52 of Fig. 9) so that the bell cranks 54 of the earlier embodiment are eliminated.

The construction illustrated in Figs. 25 and 26 affords a materially more compact assembly than those illustrated in the preceding iigures. In this case detector heads ||0, ||2 and ||3` are mounted respectively upon arms II4, H5, llt` and |1 which extend radially from a hub 8 suitably secured to the supporting rod ||9. ing rods |2|, |22, |23 and |24 which correspond to the rods 24, 90 and |05 of the previously described embodiments and which are associated respectively with the detector heads H0, ||2 and |3 are pivotally connected at the lpoints |25,

The retract- |26, |21 and |28 to a sleeve |29 which is mounted upon the upper end of the hub ||8 for angular movement about the rod |I9. The sleeve |29 is provided also with an arm |3| to which is connected a rod |32 by means of which the sleeve |29 may be rotated to retract the detector elements of the respective heads in the manner previously described.

We claim:

1. In a detector device of the character described, a detector head comprising a base, a member slidably supported in said base, a spring attached to said member and to the base and tending to retain the member in an advanced p0- sition on the base, means for retracting the member in opposition to the spring, a spring-pressed detector ringer, a pivoted element slidably supporting said finger and means for releasably retaining said element in a predetermined normal position on the pivot, an electric switch, and means for operatively connecting the switch and pivoted element so that the switch is actuated by angular displacement of the said element from the normal position, and means responsive to retraction of said member for returning the said element to the normal position.

2. A detector head according to claim 1, wherein the finger supporting element is supported on the slide member.

3. A detector head according to claim 2, wherein the switch elements are mounted on the base, a switch actuating element carried by the slide member and operative to actuate the switch upon a partial retraction of said member, and means including a fixed abutment for the linger-supporting element for so partially retracting the slide member when the said supporting element is displaced from the normal position.

4. A detector head according to claim 3 wherein a spring is operatively connected with the switch and tends to retain the switch elements in predetermined relative position, said switch actuating element moving one of the said elements against the action of the spring to actuate the switch.

tain the element in the normal position, a switch control member, a spring tending to move said control member to an extended switch actuating position, and means on said control member operative in the extended position of the latter to retain the linger-supporting element in a position displaced from the normal against action of the spring tending to return said element to the normal position.

7. A detector head according to claim 6 wheref in interlocking means is provided upon the ringersupporting element and control means and operative only when the said element is in the normal position to lock the control member in a retracted position.

8. A detector head according to claim '1 wherein means is provided for moving the control member from extended to retracted position when the slide member is retracted;

9. A detector head according to claim 8 wherein the switch is open when the control member is retracted and closed when the said member is extended.

10. In a detector device of the character described, the combination with a plurality of detector heads arranged in relatively spaced annular series, each said head comprising at least one longitudinally movable detector nger disposed-approximately radially to the center of the annulus defined -by said heads and resilient means for urging the finger toward an advanced position, a' member movable approximately radially with respect to the center of said annulus and means for normally retaining said member in an advanced position relatively remote to said center, means'` for pivotally supporting the detector nger on said member for angular movements approximately in the plane of said annulus, means for releasvably retaining the finger in a predetermined normal position with respect to -said angular movement, means for returning the linger to the normal position following angular displacement, said return means including means for retracting the movable iinger-supporting member together with relatively fixed nger-deflecting means located in the path of the finger when retracted with said member, and a cmion actua ator for the said retracting means of all of said heads.

11. A detector device according to claim 10 wherein the common actuator for the retracting means includes a single actuator member angularly movable about the center of the said annulus.

ALFRED CRAWFORD. MICHAEL ANTONEVICH.

REFERENCES CITEDk The following references are of record in the le of this patent:

UNITED STATES PATENTS 

